To study the effect of glutathione (GSH) on expression of murine CD4 and CDS in splenic lymphocytes, as a model system. Murine splenic lymphocytes were cultured in vitro for 48-72 h with or without GSH or with L-buthionine-(S,R)-sulfoximine (BSO), an inhibitor of de novo GSH synthesis, and then treated with fluorescein isothiocyanate-labeled anti-murine CD8 or phycoerythrin-labeled anti-murine CD4 antibodies. The cells were then analyzed on a FACStar Plus (Becton Dickinson) flow cytometer. The frequency and intensity of the eCD4+ and CD8 cells cultured with and without GSH or BSO were compared. Elevation of cellular GSH increases the expression of CD4 and CDB receptors in murine lymphocytes. This result provides indirect support for the hypothesis that depletion of cellular GSH contributes to the immune dysfunction in AIDS.